Unable to upgrade 'Migrate Plus'

You should specify new major version to upgrade it with drush:

For example:

drush dl
-7.x-1.x-dev

Adding my voice to this one as well. I'd love to apply some patches via composer, patches that are pretty much ready for primetime but for the lack of tests, but every time I do that I end up reverting to 2.0.0-beta2. Is this just a matter of informing Drupal's Packagist that there's a new version out there?

Can someone post a gist link to their composer.json AND composer.lock?

Here's a gist of my composer files: https://gist.github.com/tmountjr/57de945ecc2e1d317959078b99d431b8

I cannot reproduce the issue using those files.

composer update --with-dependencies

diff --git a/composer.json b/composer.json
index 1cdf651..3c12cc8 100644
--- a/composer.json
+++ b/composer.json
@@ -46,8 +46,8 @@
         "drupal/media_entity_video": "^1.0@beta",
         "drupal/menu_block": "^1.4",
         "drupal/metatag": "^1.1",
-        "drupal/migrate_plus": "^2.0",
-        "drupal/migrate_tools": "dev-4.x",
+        "drupal/migrate_plus": "^3",
+        "drupal/migrate_tools": "4.x-dev",
         "drupal/module_filter": "^3.0",
         "drupal/paragraphs": "^1.1",
         "drupal/path_redirect_import": "^1.0@beta",

#8 got me up and running on the beta 4 branch:

"drupal/migrate_plus": "^4",
"drupal/migrate_tools": "4.x-dev"

However, on a new project, I'm still getting 2.x-dev when installing for the first time:

ubuntu@devserver:/var/www/d8sandbox$ composer require drupal/migrate_plus
Using version ^2.0 for drupal/migrate_plus
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Package operations: 1 install, 0 updates, 0 removals
  - Installing drupal/migrate_plus (2.0.0-beta2): Loading from cache
> Drupal\Core\Composer\Composer::vendorTestCodeCleanup
Writing lock file
Generating autoload files
> Drupal\Core\Composer\Composer::preAutoloadDump
> Drupal\Core\Composer\Composer::ensureHtaccess

I've never gotten out-of-date betas for other projects when using composer the first time out the gate; webform, for instance, is still in beta (17 I think as of now) and I still get the most recent beta when requiring that module. While I understand you can specify a version when using composer require, my point is that you shouldn't have to in order to get the most recent package.

We ran into the same problem, any idea how we can get the latest version? We tried using
composer require migrate_plus:4-x.dev but it just throws an error

Problem 1
    - The requested package migrate_plus could not be found in any version, there may be a typo in the package name.

@yongt9412 - try composer require drupal/migrate_plus:^4 - for Drupal packages you have to include the drupal/ part of the module name.

New release provided. Let's say that the passing of time has probably fixed this issue?